Transgenic chickens get bird flu without passing it on

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Researchers have engineered a new type of chicken that might help prevent the spread of bird flu—a worrisome virus that has already caused extensive economic harm on farms, especially in Asia, and that could lead to a pandemic in humans.

Many farmers have gone to great lengths to prevent a poultry-based pandemic, but the newest results are "a significant first step along the path to developing chickens that are completely resistant to avian flu," Lawrence Tiley, a molecular virologist from the University of Cambridge’s Department of Veterinary Medicine, said in a prepared statement.

Usually kept in close quarters, chicken flocks are prone to rapid spread of viruses. The new study, published online January 13 in Science, describes a genetic trait that seems to prevent chickens from sickening their feathered neighbors, which could also reduce the risk that the flu would jump to humans, as has occurred with sporadic cases of H5N1 since 1997.

The gene makes "an innocuous decoy RNA" that closely resembles the viral genome. This decoy molecule tricks the virus into replicating it instead of producing more viral material. Incorporating the gene that makes this molecule into poultry, the research team found that although birds can still get—and even die from—the flu, they do not pass it on to nearby non-transgenic chickens.

"The decoy mimics an essential part of the flu virus genome that is identical for all strains of influenza A," said Tiley, who co-authored the new study. The RNA that the gene generates is so general that it should work against all forms of the flu—year after year—rather than needing to be reconfigured like the influenza vaccines currently administered to chicken flocks, the researchers concluded.

Crops that are genetically modified (GM) can boost yield, increase nutritional value and stave off disease, but they have been met with opposition from numerous corners. Researchers themselves continue to learn more about how these introduced genes play out in the broader environment over time. Although limited in some parts of the globe, GM crops are widespread in the U.S., and one 2010 report showed that transgenic crops were expanding to grow beyond their tended fields.

How this technology and its regulation will play out on the animal side of agriculture remains to be seen. The U.S. Food and Drug Administration has been reviewing the case for GM salmon that grow more quickly than typically farmed Atlantic salmon. And the researchers behind the new study suggested that the chicken strategy might be replicable in other domestic reservoir species, such as ducks, pigs and turkeys.

Some proponants of GM animal research play up the public health angle. "Infectious diseases of livestock represent a significant threat to global food security and the potential of pathogens, such as bird flu, to jump to humans and become pandemic has been identified by the government as a top-level national security risk," Douglas Kell, chief executive of the U.K.’s Biotechnology and Biological Sciences Research Council, which backed the study, said in a prepared statement.

The researchers also noted in their paper that unlike a vaccine, this genetic tactic is unlikely to prompt resistance in bird flu because overcoming the gene’s decoy RNA would necessitate substantial changes in all of the virus’s eight genome segments, which, they concluded, is "a statistically highly improbable event."

But meat from these GM birds is unlikely to show up in chicken nuggets any time soon. "These particular birds are only intended for research purposes, not for consumption," Tiley said.

16 Comments

Hate to break it to you but if you eat anything with corn ,soybeans, or potatoes in it, you’ve eaten GM food. If human beings want to feed the world’s population with healthy and safe food, Genetic Modification is a necessity.
Why are people so scared of chemistry and biology? Is it because people are naturally scared of anything they don’t understand?
Genetically modified foods are not the bogeyman. Disease, malnutrition, and starvation are REAL problems that we’re facing right now around the world.

I would have gone a couple of steps further. Yes, this is a good idea, however, RNAi of the gene in question would make it that much more effective. This necessary gene would be entirely absent in the new viral particles because it would be sliced up before it ever got there. The dummy gene is still an amazing idea though, I don’t see why both wouldn’t work.

Also, I would try to make it only produce this particular bit of RNA when exposed to the virus. If we can make goats that produce spider silk only in their mammary glands, I don’t see why this isn’t possible. The reason why is simple, while this bit of junk RNA might not transcribe into anything important, the resultant protein might have some sort of negative impact on health. By limiting the amount they’re exposed, you limit the potential damage. You would also quiet the crazy anti-GM crowd because more than likely, they would be exposed to little if any of the products of these genes.

Lastly, I want to be immune to the flu. Where do I sign up for that gene therapy trial?

Quoth Nathaniel:
"You would also quiet the crazy anti-GM crowd because more than likely, they would be exposed to little if any of the products of these genes."

Here’s the problem, O’ Enlightened One. Science has had to come back, countless times, from telling people no harm will be done to them, to all of a sudden being told that cancer is in their future. Why? Because you people are actually the crazy ones. You like to think there is no God because you simply can’t prove it. There is though and you are not he/she/it.

Science continues to give us great things, but when it comes to mucking around with things that go in our bodies, you just don’t know what the hell you’re doing. Your motives are fine, but that means crap to a Mom dying of cancer because of what Science has wrought.

I agree that GM crops offer us the opportunity to feed more people and provide a better quality of life and improved health to the malnourished. I work in a university lab focusing on rice and potato (via experimentation with Arabidopsis), and one of the major applications is in fact to provide hardier rice to developing nations, sometimes enriched with important nutrients. This was the well-known case with "Golden Rice," which yields a higher beta-carotene produce.

However, it can become a vicious cycle – with more food, there will be increases in population. Before introducing greater agricultural yield, we need to seriously consider population growth limits worldwide, not just in developing nations but here in the US as well. It is a touchy, often taboo subject but as a global nation we are already facing the consequences. Even with ideal GM technology, a carrying capacity will still be enforced, if not by us, then by the natural world.

Superstitious people has forever hampered progress.
Because "us people’ can’t prove god and the voices you hear in your head, you think we are the fools?
When you complain about cancer, do you think its the scientists or is it "god" that cause it? Have you seen the trend in life expectancy lately? ‘Us people’ thank science for it. "God" didn’t heal so many people before science, did he?

Scientists destroying the world? Really? So you don’t drive a car, take flights to various places, use plastics in your day to day life, use electronics (oh my bad you had to do that to post here)? Seriously? Don’t blame scientists for all the ills of the world. Science has done far more to keep people alive and healthy than any other tool at our disposal.

Your post does a great job showing how ridiculously ignorant you are, but doesn’t do a lot to sway my opinion.

You’re quick to blame science for Mom dying. Where’s your proof? Hmmm, you might actually need science to get proof of that. Of course you don’t like science, so I guess you have to abandon that line of reason. Which means you don’t get to claim science did jack to your mom. If you want to have a reasoned argument then you gotta play by the rules. You don’t get to assign blame without evidence when you spend your posts deriding an evidence based approach to things (IE SCIENCE).

For the record not all scientists are anti-religious. Many are very devout. Again you are showing ignorance by throwing out unwarranted stereotypes. My suggestion to you? Go out and learn a few things. Maybe use the car or mass transit system where you live to go to a library. Maybe spend an hour or two evaluating your arguments. Hey you might even be able to come up with one where you can prove your point without using science! Tell us God did it! That way you won’t have to think at all!

I see where you’re coming from. Ideally education, and wide spread efforts to eliminate poverty would help a lot. Particularly improvements aimed at the lot of women. Women with more choice and economic well being in third world countries tend to have fewer children.

Draconian measures need not be taken, and I certainly hope no one decides they are ever necessary. As for carrying capacity yes there is an upper limit and we are approaching it rapidly if we aren’t already there. I think, however, that every effort should be made to improve the lot of humanity. Failing to make an effort is the same ethically, as deciding to let large numbers of people starve. I don’t believe, as I’ve said, that this is necessary. In areas where standard of living and education for women have improved dramatically child birth rates have dropped.

Stinky is right to suggest that these modified chickens may have unforeseen side effects if they become our diet. The point that science flips flops back and forth on what is safe in not moot.

Stinky is wrong about God though. God is just a result of the natural Human ability to see agency in natural events. It’s a useful skill for operating in the social world. Please be nice to Stinky about God because saying there isn’t one is very threatening to Stinky as the mechanism for belief is based off the same as for social interaction.

You are correct on both counts. When they introduced rabbits in Australia it seemed like a good idea. 150 years later we still can’t cope with the problem. Vast areas have been decimated and damage runs to millions every year. Similar dangers may lurk in GM – the unforseen side effects.
Superstitious hysteria has been costly over the years but responsible caution is recommended. We have to rely on science to lead us through it though, it’s still the only reliable mechanism we have.

It is nice to know that these beasties are not being introduced into the general population. Hopefully they will be tested over several generations for basic safety. Then they would need to be tested for impact on humans that consume them.

Nathaniel, you probably don’t want to sign up any time soon, unless altruistic self-sacrifice is your thing. The article says the gengineered chickens didn’t pass the flu to their neighbours, but got sick and even died of it themselves. Ouch!